Address PR review feedback (#1741)

- Close first TaskStore before creating second in interactive registration (P1)
- Revert defaultWorkflowId default to undefined; set explicitly in onboarding only (P1)
- Add alpha-only filter + 2-char min to interactive prefix input (P2)
- Move suggestTaskPrefix to @fusion/core, share between CLI and dashboard (P2)
- Fix suggestTaskPrefix JSDoc to match implementation (P2)

packages/cli/src/project-resolver.ts

@@ -18,6 +18,7 @@ import {
   writeProjectIdentity,
   detectWorkspaceRepos,
   saveWorkspaceConfig,
+  suggestTaskPrefix,
   type RegisteredProject,
   type TaskStore,
 } from "@fusion/core";
@@ -537,19 +538,6 @@ export function suggestProjectName(path: string): string {
   return parts[parts.length - 1] || "unnamed";
 }
 
-/**
- * FNXC:TaskPrefix 2026-06-24-18:00:
- * Derive a task prefix from a project name by taking the first 2-4 uppercase
- * letters. Falls back to "FN" for short names. Used as the suggested default
- * during project onboarding so each project gets a recognizable prefix.
- */
-export function suggestTaskPrefix(projectName: string): string {
-  const cleaned = projectName.replace(/[^a-zA-Z]/g, "").toUpperCase();
-  if (cleaned.length >= 2 && cleaned.length <= 4) return cleaned;
-  if (cleaned.length > 4) return cleaned.slice(0, 4);
-  return "FN";
-}
-
 /**
  * Resolve absolute path and validate it exists.
  */
@@ -698,6 +686,7 @@ export async function registerProjectInteractive(
           // Persist workspaceMode in config.json so it's visible/toggleable in the dashboard
           await store.updateSettings({ workspaceMode: true });
         }
+        await store.close();
         console.log(`  ✓ Initialized fn at ${absPath}`);
       } else {
         throw new ProjectResolutionError(
@@ -772,7 +761,8 @@ export async function registerProjectInteractive(
     const rl = createInterface({ input: process.stdin, output: process.stdout });
     const prefixInput = await rl.question(`\n  Task prefix [${suggestedPrefix}]: `);
     rl.close();
-    const prefix = prefixInput.trim().toUpperCase() || suggestedPrefix;
+    const rawPrefix = prefixInput.trim().toUpperCase().replace(/[^A-Z]/g, "");
+    const prefix = rawPrefix.length >= 2 ? rawPrefix : suggestedPrefix;
 
     await store.updateSettings({
       taskPrefix: prefix,

packages/core/src/index.ts

@@ -1957,3 +1957,4 @@ export {
   clearSyncPassphrase,
   hasSyncPassphraseConfigured,
 } from "./secrets-sync-passphrase.js";
+export { suggestTaskPrefix } from "./task-prefix.js";

packages/core/src/settings-schema.ts

@@ -258,7 +258,7 @@ export const DEFAULT_GLOBAL_SETTINGS = {
 export const DEFAULT_PROJECT_SETTINGS = {
   globalPause: false,
   globalPauseReason: undefined,
-  defaultWorkflowId: "builtin:coding",
+  defaultWorkflowId: undefined,
   enabledBuiltinWorkflowIds: undefined,
   approvedWorkflowCliCommands: undefined,
   approvedCliAutonomyAdapters: undefined,

packages/core/src/task-prefix.ts

@@ -0,0 +1,17 @@
+/**
+ * FNXC:TaskPrefix 2026-06-24-18:00:
+ * Derive a task prefix from a project name. Strips non-alpha characters, uppercases,
+ * and takes the first 2-4 characters. Falls back to "FN" for names with fewer than
+ * 2 letters. Used during project onboarding (CLI and dashboard) so each project gets
+ * a recognizable prefix for task IDs (e.g. "MYPR" for "my-project").
+ *
+ * Note: the result is the first 2-4 letters of the cleaned (alpha-only, uppercased)
+ * name, NOT the initials of each word. For "my-project" the result is "MYPR"
+ * (first 4 of "MYPROJECT"), not "MP".
+ */
+export function suggestTaskPrefix(projectName: string): string {
+  const cleaned = projectName.replace(/[^a-zA-Z]/g, "").toUpperCase();
+  if (cleaned.length >= 2 && cleaned.length <= 4) return cleaned;
+  if (cleaned.length > 4) return cleaned.slice(0, 4);
+  return "FN";
+}

packages/dashboard/src/routes/register-project-routes.ts

@@ -382,10 +382,10 @@ export const registerProjectRoutes: ApiRouteRegistrar = (ctx) => {
       */
       if (activeProjectWithOutcome.outcome === "registered") {
         try {
-          const { TaskStore } = await import("@fusion/core");
+          const { TaskStore, suggestTaskPrefix } = await import("@fusion/core");
           const store = new TaskStore(normalizedPath);
           await store.init();
-          const prefix = normalizedName.replace(/[^a-zA-Z]/g, "").toUpperCase().slice(0, 4) || "FN";
+          const prefix = suggestTaskPrefix(normalizedName);
           await store.updateSettings({
             taskPrefix: prefix,
             defaultWorkflowId: "builtin:coding",